Medical probes such as endoscopes are used for examining and treating internal body structures such as the alimentary canals, airways, the gastrointestinal system, and other organ systems. Endoscopes have attained great acceptance within the medical community since they provide a means for performing procedures with minimal patient trauma, while enabling the physician to view the internal anatomy of the patient. Over the years, numerous endoscopes have been developed and categorized according to specific applications, such as cystoscopy, colonoscopy, laparoscopy, upper gastrointestinal (GI) endoscopy and others. Endoscopes may be inserted into the body's natural orifices or through an incision in the skin.
An endoscope usually comprises an elongated tubular shaft, rigid or flexible, having a video camera or a fiber optic lens assembly at its distal end. The shaft is connected to a handle, which sometimes includes an ocular lens or eyepiece for direct viewing. Viewing is also usually possible via an external screen. Various surgical tools may be inserted through a working channel in the endoscope for performing different surgical procedures.
In an electronic endoscopy system, the main control unit, which is used to process data from an endoscope, is generally a separate unit while the endoscope itself is a device that can be attached to the main control unit. The main control unit comprises a front panel and/or a display screen for displaying operational information with respect to an endoscopy procedure when the endoscope is in use. The display screen may be configured to display images and/or video streams received from the viewing elements of the multiple viewing elements endoscope.
In recent years, there has been an increasing demand for improving the image quality of medical probes, such as endoscopes, to enhance in the accuracy of a diagnosis. A majority of the endoscopic devices available in the market have limited magnification power. During an endoscopic procedure, physicians often want to focus on a specific area in the human body to analyze the same in more detail. They are, however, constrained by the limited magnification power of the endoscopic devices to enlarge or zoom an area of interest. The technical limitations as a result of the small size of endoscopic devices make it difficult to dynamically enhance magnification power in these devices.
Usually, in a typical, non-endoscope imaging apparatus, dynamic image magnification is achieved by either moving the complete objective lens assembly or through relative motion between specific groups of lenses. In an endoscopic device, usually, it is not possible to move the complete objective lens assembly as the barrel surrounding the lens assembly is fixed within the endoscope so that it can be appropriately sealed.
In conventional objective lens systems, the magnification is achieved by relative motion between separate groups of lenses. In such systems, a lens group is moved to change a state of the objective optical system suitable for normal observation state into a state of the objective optical system suitable for close-up observation so that the objective optical system is closer to a particular object optionally selected from a plurality of objects present in an observation area by an observer to make it possible to observe the particular object in detail. In endoscopy systems, because of the miniature size of such devices, providing activators for enabling movement of separate groups of the lens assembly as described above makes the overall system very complicated and hence it is not possible to provide a very high magnification capability in such devices. The conventional endoscopy systems are thus usually constrained as far as their as their magnification power is concerned.
There is a need for addressing the above-mentioned limitation in medical probes, such as endoscopes, to enhance the quality of medical procedures conducted using such devices. There is a need for providing endoscope systems with dynamic magnification capabilities which are easy to implement in a miniaturized environment and have a robust structure.